The present invention relates to a cambering vehicle of the type having a single front wheel extending from a vertical steering stem's lower extremity and two rear wheels, each attached to one of a pair of horizontal trailing arms pivotally attached to the steering stem. Typically, handlebars attach to the steering stem's upper extremity to permit manipulation of the single wheel. Above the rear wheels on each of the trailing arms are platforms for the user to stand on while operating the vehicle. More particularly, the cambering vehicle of the present invention also includes a novel structure which may be readily folded for storage or transport, for example. Another embodiment of the cambering vehicle of the present invention includes a novel crossbar member spanning the two trailing arms.
Various conventional cambering vehicles have been developed. Such conventional vehicles are generally operator propelled three wheeled vehicles comprising a front column having a steering shaft rotatably attached thereto, a front wheel attached to the bottom of the steering shaft, and a pair of laterally spaced rear wheels on trailing arms which are articulated to the front column. More complex vehicles also include additional elements, including brakes.
To move the vehicle, the operator stands upon platforms provided on each trailing arm. By alternately leaning left and right, the vehicle will camber left and right. This cambering induces a force between the rear wheels and a surface upon which the vehicle is placed. The force produces work driving the vehicle forward along a sinusoidal path, the frequency of which is related to the user's input of alternate leans and the amplitude of which is related to the speed of the vehicle.
More recent of the conventional cambering vehicles are designed to be folded into a compact configuration for storage or transport, for example. Several of the prior art cambering vehicles fold at the connection of the steering stem and the trailing arms. Other vehicles have trailing arms with intermediate folding mechanisms. Such vehicles often suffer from the application of unwanted flexing within the trailing arm. Also, such folding mechanisms typically include quick-release type features, which may cause folding of the device at inadvertent times, or which may be difficult to operate.
The trailing arms of conventional vehicles have their front ends rotatably or pivotally secured to the front column by utilizing an attachment fitting or shaft that is perpendicular to the front column. When the vehicle is cambered toward one side, such as the right side, the left trailing arm and thus the left rear wheel may be forced or caused to be moved upwardly away from the ground, or may not be suitably contacted with the ground.
Conversely, when the vehicle is cambered toward the other side, for example the left side, the right trailing arm and thus the right rear wheel may also be forced or caused to be moved upwardly away from the ground, or may not be suitably contacted with the ground, such that the vehicle may not be stable as it travels along the sinusoidal path.
Aspects of the present invention mitigate and/or obviate the aforementioned disadvantages of the conventional cambering vehicles.